[moderation] [pm?] KCSAN: data-race in __pm_runtime_resume / pm_runtime_work (2)

[syzbot]

Hello,

syzbot found the following issue on:

HEAD commit: 7839932417dd Merge tag 'sched_ext-for-6.19-rc3-fixes' of g..
git tree: upstream
console output: https://syzkaller.appspot.com/x/log.txt?x=136a4422580000
kernel config: https://syzkaller.appspot.com/x/.config?x=b319ff1b6a2797ca
dashboard link: https://syzkaller.appspot.com/bug?extid=4e913557b88c24bb2448
compiler: Debian clang version 20.1.8 (++20250708063551+0c9f909b7976-1~exp1~20250708183702.136), Debian LLD 20.1.8
CC: [da...@kernel.org gre...@linuxfoundation.org le...@kernel.org linux-...@vger.kernel.org linu...@vger.kernel.org pa...@kernel.org raf...@kernel.org]

Unfortunately, I don't have any reproducer for this issue yet.

Downloadable assets:
disk image: https://storage.googleapis.com/syzbot-assets/1215db8aa742/disk-78399324.raw.xz
vmlinux: https://storage.googleapis.com/syzbot-assets/ec810c593e84/vmlinux-78399324.xz
kernel image: https://storage.googleapis.com/syzbot-assets/39a26f9ca191/bzImage-78399324.xz

IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+4e9135...@syzkaller.appspotmail.com

==================================================================
BUG: KCSAN: data-race in __pm_runtime_resume / pm_runtime_work

write to 0xffff888101d9f268 of 2 bytes by task 3663 on cpu 1:
pm_runtime_work+0x90/0x130 drivers/base/power/runtime.c:989
process_one_work kernel/workqueue.c:3257 [inline]
process_scheduled_works+0x4ce/0x9d0 kernel/workqueue.c:3340
worker_thread+0x582/0x770 kernel/workqueue.c:3421
kthread+0x489/0x510 kernel/kthread.c:463
ret_from_fork+0x149/0x290 arch/x86/kernel/process.c:158
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:246

read to 0xffff888101d9f268 of 2 bytes by task 5506 on cpu 0:
__pm_runtime_resume+0x35/0x100 drivers/base/power/runtime.c:1190
pm_runtime_get_active include/linux/pm_runtime.h:520 [inline]
pm_runtime_resume_and_get include/linux/pm_runtime.h:539 [inline]
usb_autoresume_device+0x23/0xc0 drivers/usb/core/driver.c:1760
usbdev_open+0x121/0x450 drivers/usb/core/devio.c:1058
chrdev_open+0x2eb/0x3a0 fs/char_dev.c:414
do_dentry_open+0x54b/0xa60 fs/open.c:962
vfs_open+0x37/0x1e0 fs/open.c:1094
do_open fs/namei.c:4628 [inline]
path_openat+0x1ddd/0x23b0 fs/namei.c:4787
do_filp_open+0x109/0x230 fs/namei.c:4814
do_sys_openat2+0xa6/0x150 fs/open.c:1430
do_sys_open fs/open.c:1436 [inline]
__do_sys_openat fs/open.c:1452 [inline]
__se_sys_openat fs/open.c:1447 [inline]
__x64_sys_openat+0xf2/0x120 fs/open.c:1447
x64_sys_call+0x2b07/0x3000 arch/x86/include/generated/asm/syscalls_64.h:258
do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
do_syscall_64+0xca/0x2b0 arch/x86/entry/syscall_64.c:94
entry_SYSCALL_64_after_hwframe+0x77/0x7f

value changed: 0x0890 -> 0x0888

Reported by Kernel Concurrency Sanitizer on:
CPU: 0 UID: 0 PID: 5506 Comm: syz.0.639 Not tainted syzkaller #0 PREEMPT(voluntary)
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/25/2025
==================================================================


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